8902245

Method for Driving Quad-Subpixel Display

PublishedDecember 2, 2014
Assigneenot available in USPTO data we have
InventorsWoo-Young So
Technical Abstract

Patent Claims
16 claims

Legal claims defining the scope of protection. Each claim is shown in both the original legal language and a plain English translation.

Claim 1

Original Legal Text

1. A method of displaying an image on a display, comprising: receiving a display signal that defines an image, wherein a display color gamut is defined by three sets of CIE coordinates (x RI , y RI ), (x GI , y GI ), (x sI , y BI ) the display signal is defined for a plurality of pixels; for each pixel, the display signal comprises a desired chromaticity and luminance defined by three components R I , G I and B I that correspond to luminances for three sub-pixels having CIE coordinates (x RI , y RII ), (x GI , y GI ) and (x BI , y BI ), respectively, that render the desired chromaticity and luminance; wherein the display comprises a plurality of pixels, each pixel including an R sub-pixel, a G sub-pixel, a B1 sub-pixel and a B2 sub-pixel, wherein: each R sub-pixel comprises a first organic light emitting device that emits light having a peak wavelength in the visible spectrum of 580-700 mu, further comprising a first emissive layer having a first emitting material; each G sub-pixel comprises a second organic light emitting device that emits light having a peak wavelength in the visible spectrum of 500-580 nm, further comprising a second emissive layer having a second emitting material; each B1 sub-pixel comprises a third organic light emitting device that emits light having a peak wavelength in the visible spectram of 400-500 nm, further comprising a third emissive layer having a third emitting material; each B2 sub-pixel comprises a fourth organic light emitting device that emits light having a peak wavelength in the visible spectrum of 400 to 500 nm, further comprising a fourth emissive layer having a fourth emitting material; the third emitting material is different from the fourth emitting material; and the peak wavelength in the visible spectrum of light emitted by the fourth organic light emitting device is at least 4 nm less than the peak wavelength in the visible spectrum of light emitted by the third organic light emitting device; wherein each of the R, G, B1 and B2 sub-pixels has CIE coordinates (x R , y R ), (x G , y G ), (x B1 , y B1 ) and (x B2 , y B2 ), respectively; wherein each of the R, G, B1 and B2 sub-pixels has a maximum luminance Y R , Y G , Y B1 and Y B2 , respectively, and a signal component R C , G C B1 C and B2 C , respectively; wherein a plurality of color-spaces are defined, each color space being defined by the CIE coordinates of three of the R, G, B1 and B2 sub-pixels, wherein every chromaticity of the display gamut is located within at least one of the plurality of color spaces; wherein at least one of the color spaces is defined by the R, G and B2 sub-pixels; wherein the color spaces are calibrated by using a calibration chromaticity and luminance having a CIE coordinate (x C , y C ) located in the color space defined by the R, B and B1 sub-pixels, such that: a single maximum luminance for the display is defined for each of the R, G, B1 and B2 sub-pixels, for each color space, for chromaticities located within the color space, a linear transformation is defined that transforms the three components R I , G I and B I into luminances for the each of the three sub-pixels having CIE coordinates that define the color space that will render the desired chromaticity and luminance defined by the three components R 1 , G 1 and B 1 ; displaying the image by, for each pixel: choosing one of the plurality of color spaces that includes the desired chromaticity of the pixel; transforming the R I , G I and B I components of the signal for the pixel into luminances defined relative to the maximum luminance for the display for each of the three sub-pixels having CIE coordinates that define the chosen color space; emitting light from the pixel having the desired chromaticity and luminance using the luminances resulting from the transformation of the R I , G I and B I components.

Plain English Translation

A method for displaying images on a display with red, green, light blue (B1), and deep blue (B2) sub-pixels. The method receives an image signal designed for a standard three-color (RGB) display and converts it to a format suitable for the four-sub-pixel display. The display uses organic light-emitting devices (OLEDs) for each sub-pixel, each emitting light within specific wavelength ranges: red (580-700 nm), green (500-580 nm), and two blues (B1 & B2, 400-500 nm) with the B2 wavelength being at least 4nm less than B1. The method defines multiple color spaces using combinations of the R, G, B1, and B2 sub-pixel colors. For each pixel, the method selects the color space that best represents the desired color, transforms the original RGB signal into luminance values for the sub-pixels defining that color space, and then emits light from those sub-pixels to produce the desired color and brightness. This conversion accounts for variations in sub-pixel brightness, maximizing the dynamic range.

Claim 2

Original Legal Text

2. The method of claim 1 , wherein: two color spaces are defined: a first color space defined by the CIE coordinates of the R, G and B1 sub-pixels, and a second color space defined by the CIE coordinates of the R, G and B2 sub-pixels.

Plain English Translation

The image display method, where the display utilizes red, green, light blue (B1), and deep blue (B2) sub-pixels, uses specifically two color spaces: one defined by the red, green, and light blue (B1) sub-pixels, and another defined by the red, green, and deep blue (B2) sub-pixels. The image signal designed for a standard three-color (RGB) display is then converted to a format suitable for the four-sub-pixel display.

Claim 3

Original Legal Text

3. The method of claim 2 , wherein: the first color space is chosen for pixels having a desired chromaticity located within the first color space; and the second color space is chosen for pixels having a desired chromaticity located within a subset of the second color space defined by the R, B1 and B2 sub-pixels.

Plain English Translation

The image display method using red, green, light blue (B1), and deep blue (B2) sub-pixels where two color spaces are defined (red/green/B1 and red/green/B2), the red/green/B1 color space is used for pixels whose desired colors fall within that color space. The red/green/B2 color space is used for pixels whose desired colors fall within a subset of the red/green/B2 color space that is also defined by the red, B1, and B2 sub-pixels. This allows for more precise color rendering.

Claim 4

Original Legal Text

4. The method of claim 3 , wherein the color spaces are calibrated by using a calibration chromaticity and luminance having a CIE coordinate (x C , Y C ) located in the color space defined by the R, G and B1 sub-pixels by: defining maximum luminances (Y′ R , Y′ G and Y′ B1 ) for the color space defined by the R, G and B1 sub-pixels, such that emitting luminances Y′ R , Y′ G and Y′ B 1 from the R, G and B1 sub-pixels, respectively, renders the calibration chromaticity and luminance; defining maximum luminances (Y″ R , Y″ G and Y B2 ) for the color space defined by the R, G and B2 sub-pixels, such that emitting luminances Y″ R , Y″ G and Y″ 52 from the R, G and B2 sub-pixels, respectively, renders the calibration chromaticity and luminance; defining maximum luminances (Y R , Y G , Y B1 and Y B2 ) for the display, such that Y R =max (Y R ′, Y R ″), Y′ G =max (Y G ′, Y G ″), Y B1 =Y′ B1 , and Y B2 =Y′ R2 .

Plain English Translation

The image display method using red, green, light blue (B1), and deep blue (B2) sub-pixels where two color spaces are defined (red/green/B1 and red/green/B2) calibrates the color spaces to ensure accurate color reproduction. Calibration is achieved by selecting a target color, and measuring what it takes to produce the color. Maximum luminance values are defined by how bright they are when creating the color, so the brightest values are used for the display.

Claim 5

Original Legal Text

5. The method of claim 4 , wherein: the linear transformation for the first color space is a sealing that transforms R I into R C , G I into G C , and B I into B1 C ; and the linear transformation for the second color space is a scaling that transforms R I into R C , G I into G C , and B I into B2 C .

Plain English Translation

The image display method, using red, green, light blue (B1), and deep blue (B2) sub-pixels, calibrates color spaces using linear transformations. For the first color space (R, G, B1), the linear transformation scales the red input (R I) to red output (R C), green input (G I) to green output (G C), and blue input (B I) to light blue output (B1 C). Similarly, for the second color space (R, G, B2), the linear transformation scales the red input (R I) to red output (R C), green input (G I) to green output (G C), and blue input (B I) to deep blue output (B2 C). Essentially, the color inputs are scaled for each colorspace to produce desired outputs.

Claim 6

Original Legal Text

6. The method of claim 2 , wherein the CIE coordinates of the B1 sub-pixel are located outside the second color space.

Plain English Translation

The image display method using red, green, light blue (B1), and deep blue (B2) sub-pixels where two color spaces are defined (red/green/B1 and red/green/B2), the CIE coordinates of the light blue (B1) sub-pixel fall outside the color space defined by the red, green, and deep blue (B2) sub-pixels. This placement can allow for increased color separation.

Claim 7

Original Legal Text

7. The method of claim 1 , wherein: two color spaces are defined: a first color space defined by the CIE coordinates of the R, G and B1 sub-pixels, and a second color space defined by the CIE coordinates of the R, B1 and B2 sub pixels.

Plain English Translation

The image display method, for a display with red, green, light blue (B1), and deep blue (B2) sub-pixels, defines two color spaces: one using the red, green, and B1 sub-pixels, and the other using the red, B1, and B2 sub-pixels. Image signal conversion is used to reformat for use with the four-sub-pixel architecture.

Claim 8

Original Legal Text

8. The method of claim 7 , wherein: the first color space is chosen for pixels having a desired Chromaticity located within the first color space; and the second color space is chosen for pixels having a desired chromaticity located within the second color space.

Plain English Translation

The image display method using red, green, light blue (B1), and deep blue (B2) sub-pixels where two color spaces are defined (red/green/B1 and red/B1/B2), the red/green/B1 color space is chosen for pixels with colors within that space. The red/B1/B2 color space is chosen for pixels with colors that fit inside that second color space.

Claim 9

Original Legal Text

9. The method of claim 7 , wherein the CIE coordinates of the B1 sub-pixel are located outside the second color space.

Plain English Translation

The image display method using red, green, light blue (B1), and deep blue (B2) sub-pixels where two color spaces are defined (red/green/B1 and red/B1/B2), the CIE coordinates of the light blue (B1) sub-pixel are outside the color space defined by the red, B1, and B2 sub-pixels.

Claim 10

Original Legal Text

10. The method of claim 1 , wherein: the CIE coordinates of the B1 sub-pixel are located inside a color space defined by the CIE coordinates of the R, G and B2 sub-pixels; three color spaces are defined: a first color space defined by the CIE coordinates of the R, G and B1 sub-pixels; a second color space defined by the CIE coordinates of the B2 and B1 sub-pixels; and a third color space defined by the CIE coordinates of the B2, R and B1 sub-pixels.

Plain English Translation

In an image display method with red, green, light blue (B1), and deep blue (B2) sub-pixels, the CIE coordinates of the B1 sub-pixel are located *inside* a color space defined by the red, green, and B2 sub-pixels. Three color spaces are defined: red/green/B1, B2/B1, and B2/red/B1. Image signal conversion is used to reformat for use with the four-sub-pixel architecture.

Claim 11

Original Legal Text

11. The method of claim 10 , wherein: the first color space is chosen for pixels having a desired chromaticity located within the first color space; and the second color space is chosen for pixels having a desired chromaticity located within the second color space; and the third color space is chosen for pixels having a desired chromaticity located within the third color space.

Plain English Translation

In an image display method with red, green, light blue (B1), and deep blue (B2) sub-pixels, the three colorspaces defined are: red/green/B1, B2/B1, and B2/red/B1. The red/green/B1 is chosen when the desired color fits, and the B2/B1 and B2/red/B1 colorspaces are likewise chosen for pixels with colors that fit inside those colorspaces.

Claim 12

Original Legal Text

12. The method of claim 1 , wherein the CIE coordinates are 1931 CIE coordinates.

Plain English Translation

The image display method using red, green, light blue (B1), and deep blue (B2) sub-pixels uses CIE 1931 color space coordinates for all calculations and color space definitions.

Claim 13

Original Legal Text

13. The method of claim 1 , wherein the calibration color has a CIE coordinate (x C , y C ) such that 0.25<x C <0.4 and 0.25<y C <0.4.

Plain English Translation

The image display method using red, green, light blue (B1), and deep blue (B2) sub-pixels calibrates the color spaces using a color with CIE coordinates (x C, y C) such that 0.25 < x C < 0.4 and 0.25 < y C < 0.4. This calibrates color on the display.

Claim 14

Original Legal Text

14. The method of claim 1 , wherein the CIE coordinate of the B1 sub-pixel is located outside the triangle defined by the R, G and B2 CIE coordinates.

Plain English Translation

The image display method with red, green, light blue (B1), and deep blue (B2) sub-pixels positions the CIE coordinate of the light blue (B1) sub-pixel *outside* the triangle formed by the CIE coordinates of the red, green, and deep blue (B2) sub-pixels. This allows for more precise color rendering.

Claim 15

Original Legal Text

15. The method of claim 1 , wherein the CIE coordinate of the B1 sub-pixel is located inside the triangle defined by the R, G and B2 CIE coordinates.

Plain English Translation

The image display method with red, green, light blue (B1), and deep blue (B2) sub-pixels positions the CIE coordinate of the light blue (B1) sub-pixel *inside* the triangle formed by the CIE coordinates of the red, green, and deep blue (B2) sub-pixels.

Claim 16

Original Legal Text

16. The method of claim 1 , wherein the first, second and third emitting materials are phosphorescent emissive materials, and the fourth emitting material is a fluorescent emitting material.

Plain English Translation

In the image display method, using a display with red, green, light blue (B1), and deep blue (B2) sub-pixels, the first, second, and third light emitting materials (for red, green and B1) are phosphorescent, while the fourth emitting material (for B2) is fluorescent.

Patent Metadata

Filing Date

Unknown

Publication Date

December 2, 2014

Inventors

Woo-Young So

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Cite as: Patentable. “METHOD FOR DRIVING QUAD-SUBPIXEL DISPLAY” (8902245). https://patentable.app/patents/8902245

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